This study will recruit patients aged 18-80 with refractory gastroesophageal reflux disease (GERD). These patients had a disease course of more than six months, experienced typical symptoms such as acid reflux and heartburn, and had no symptom relief after taking a double dose of acid-suppressing medication for eight consecutive weeks. All eligible participants will undergo Endoscopic Cardial Constriction Ligation (ECCL) using a disposable endoscope. The procedure will follow a standardized protocol: mucosal and muscle layers of the cardia will be ligated at the lesser curvature, posterior wall, and greater curvature, with the ligated tissue at the greater curvature secured by a hemostatic clip. All patients will receive acid-suppressing therapy post-surgery and will be followed up at three and six months. The follow-ups will assess their GERD-Q scores, symptom relief, and incidence of complications.

Gastroesophageal reflux disease (GERD) is a common digestive disorder, with endoscopic manifestations including non-erosive reflux disease (NERD), reflux esophagitis (RE), and Barrett's esophagus (BE). Typical symptoms include heartburn and regurgitation, while atypical symptoms encompass chest pain, epigastric pain, belching, and extraesophageal symptoms. Epidemiological surveys in China indicate a prevalence of heartburn occurring at least once weekly ranging from 1.9% to 7.0%. Chronic, recurrent GERD significantly impairs patients' quality of life and may increase the risk of Barrett's esophagus, esophageal mucosal dysplasia, and esophageal adenocarcinoma. The etiology of GERD is complex, involving increased esophageal acid exposure, lower esophageal sphincter (LES) relaxation, low esophagogastric junction (EGJ) pressure, impaired esophageal clearance, hiatal hernia, and damage to the mucosal barrier by cytokines (e.g., IL-6, IL-8, platelet-activating factor PAF) and other factors.

Currently, the first-line treatment for GERD includes lifestyle modifications and oral acid-suppressive medications, such as proton pump inhibitors (PPIs) and potassium-competitive acid blockers (P-CABs). However, some patients with refractory GERD require long-term acid-suppressive therapy, and prolonged PPI use may increase the risk of Clostridioides difficile infection, community-acquired pneumonia, gastric cancer, and chronic kidney disease, while short-term P-CAB use may lead to hypergastrinemia [13]. According to the 2020 Chinese GERD Expert Consensus, for patients with refractory GERD who fail medical therapy, endoscopic or surgical treatment may be considered after excluding other causes and confirming evidence of reflux.

Traditional endoscopes are reusable and require cleaning and disinfection after each use, but complete sterilization may not always be achieved, posing a risk of cross-infection. In contrast, disposable endoscopes eliminate the risk of cross-infection, bypass the need for cleaning and disinfection, and reduce the incidence of instrument-related infections, while offering comparable functionality and operability to traditional endoscopes. Endoscopic cardia constriction ligation (ECCL) is an emerging endoscopic treatment technique, first performed by Professor Linghu Enqiang in 2013. This procedure involves ligating and fixing the mucosa and partial muscle layer above the dentate line under direct endoscopic visualization, creating mucosal folds. Post-procedure, the ligated mucosa undergoes ischemic necrosis and heals to form scar tissue, reducing the cardia diameter, increasing LES pressure, and alleviating reflux symptoms. ECCL is characterized by simple operation and minimal invasiveness, making it safer than traditional surgical procedures. Related complications, such as bleeding after ligation band detachment and retrosternal pain, are infrequent, resolve quickly, and no severe adverse events have been reported to date. However, the long-term efficacy of ECCL requires further validation.

Currently, there are no studies on the efficacy and safety of ECCL performed using disposable endoscopes. This study aims to conduct a randomized controlled trial to compare the effectiveness, safety, flexibility, and imaging clarity of ECCL performed with disposable versus traditional endoscopes in treating refractory GERD, providing scientific evidence to optimize treatment strategies and inform future GERD treatment guidelines.

Participants in this study will be randomly assigned to either the disposable endoscope group or the traditional endoscope group to undergo ECCL treatment. The primary objective is to compare the efficacy of ECCL performed with disposable versus traditional endoscopes in treating refractory GERD. Secondary objectives include: 1) Evaluating the observation clarity, flexibility, and compatibility of disposable endoscopes with surgical consumables; 2) Assessing the incidence of device failures and complications related to disposable endoscope-guided ECCL, such as mucosal injury, bleeding, and perforation.

Inclusion Criteria:

• (1) Age 18-80 years;
• (2) Disease duration ≥6 months, with typical symptoms such as acid regurgitation and heartburn, and a confirmed diagnosis of GERD;
• (3) GERD patients whose symptoms are not relieved after 8 weeks of continuous double-dose acid-suppressive therapy;
• (4) Willing to participate in the study and have signed the informed consent form.

Exclusion Criteria:

• (1) Patients with precancerous lesions such as early esophageal cancer or Barrett's esophagus >3 cm, or advanced upper gastrointestinal cancer identified on endoscopy;
• (2) Patients with hiatal hernia ≥2 cm, severe reflux esophagitis (LA-C or LA-D grade), esophageal or gastric varices, esophageal ulcer or stenosis, or a history of esophageal or gastric surgery;
• (3) Patients with esophageal motility disorders such as achalasia or diffuse esophageal spasm, rheumatic diseases such as systemic sclerosis or Sjögren's syndrome, or eosinophilic esophagitis;
• (4) Patients with a history of endoscopic or surgical anti-reflux procedures;
• (5) Patients with coagulation disorders, severe cardiopulmonary diseases, or inability to tolerate anesthesia, endoscopy, or treatment;
• (6) Women in the puerperium.